Apple Safari before 6.0 does not properly handle the autocomplete attribute of a password input element, which allows remote attackers to bypass authentication by leveraging an unattended workstation.
http://www.securityfocus.com/bid/54688
http://support.apple.com/kb/HT5503
http://support.apple.com/kb/HT5400
http://lists.apple.com/archives/security-announce/2012/Sep/msg00003.html
http://lists.apple.com/archives/security-announce/2012/Jul/msg00000.html